Support unit utilized in visual inspection of display substrate

ABSTRACT

Disclosed is a support unit for visually inspecting a display substrate, such as an LCD device, that enhances accuracy of the inspection by supporting the display substrate at dummy regions between cell areas. The support unit includes fixed bars disposed apart from each other and along a first direction; a plurality of support bars connected to the fixed bars, the support bars oriented along a second direction crossing the first direction and movable along the first direction; a guide bar mounted on at least one of the support bars, the guide bar oriented along the first direction and movable along the second direction; first and second auxiliary support bars connected to the guide bar, the auxiliary support bars oriented along the second direction and movable along the first direction; and a plurality of supporting means disposed on the support bars and the auxiliary support bars.

This application claims the benefit of Korean Patent Application No.2003-100326, filed on Dec. 30, 2003, which is hereby incorporated byreference for all purposes as if fully set forth herein.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention generally relates to a support unit that isutilized in a visual inspection of display substrates. Moreparticularly, the present invention relates to a support unit that caneffectively support a display substrate having various size cell regionsin the visual inspection.

2. Discussion of the Related Art

A display substrate refers to a display device having a transparent basesubstrate such as a glass. A liquid crystal display (LCD) device is anexample of a typical display device.

An LCD device includes an array substrate having a thin film transistor(TFT), a color filter substrate having a color filter layer, and aliquid crystal layer that is interposed between the array substrate andthe color filter substrate. An LCD device is formed through processesincluding an array process for forming the array substrate, a colorfilter process for forming the color filter substrate, a cell processfor interposing the liquid crystal layer between the array substrate andthe color filter substrate, and a module process that includes a step ofattaching polarizers on outer sides of the array substrate and the colorfilter substrate.

Thin film patterns are formed in the array and color filter processesthrough depositing (or coating), photolithography including exposing anddeveloping, and etching procedures. In addition, the cell processincludes forming an alignment layer on the inner surface of each of thearray substrate and the color filter substrate; rubbing the alignmentlayer; scattering a spacer on either the array substrate or the colorfilter substrate; attaching the array substrate and the color filtersubstrate; and interposing the liquid crystal layer by, for example,injecting the liquid crystal material between the array substrate andthe color filter substrate. The array substrate, the color filtersubstrate, and the liquid crystal layer form an LCD panel. Moreover, themodule process includes a final step in which production quality of theLCD panel is determined by inspection, polarizers are attached to theLCD panel, various circuitry is integrated with the LCD panel, and thebacklight is installed.

A visual inspection of the LCD panel is performed after the cell processand before the module process. Through the visual inspection process,spots or particles that are found due to a spacer defect can be removed.The visual inspection includes preparing a support unit, disposing theLCD panel on the support unit, and setting the support unit to supportthe LCD panel. The visual inspection further includes radiatinginspection light into the LCD panel and measuring a uniformity ofinspection light that is transmitted into the LCD cell. Specifically,the LCD panel for inspecting may include polarizers on outer sides ofthe LCD panel. Visual inspection may be performed on the stand-alone LCDpanel, or on a display substrate including the LCD panel.

FIG. 1 is a schematic perspective view of a support unit utilized in avisual inspection of a display substrate according to the related art.The display substrate (not shown) includes a transparent base substratesuch as a glass.

In FIG. 1, first and second fixed bars 10 and 12 are disposed apart fromeach other and are oriented along a first direction. A plurality ofsupport bars 14 are connected to both of the first and second fixed bars10 and 12 and are oriented along a second direction crossing the firstdirection. The plurality of support bars 14 are movable along the firstdirection. In addition, a plurality of supporting means 16 that directlycontact a display substrate (not shown), or the object of the visualinspection, are mounted on the plurality of the support bars 14.

FIG. 2 is a schematic plan view illustrating a support structure of FIG.1 supporting a multi-model type display substrate according to therelated art. The multi-model type display substrate may be defined as adisplay substrate that has multiple cell areas arranged on it forincreasing space efficiency.

In FIG. 2, a display substrate 20 has a plurality of first cells 22having a first active area AA1 and a plurality of second cells 24 havinga second active area AA2 smaller than the first active area AA1. Thesecond cells 24 may be formed to reduce a dummy region DR between thefirst cells 22. That is, the display substrate 20 includes first cells22, second cells 24 and dummy region DR.

To effectively support the display substrate 20 by the support unit 18before the visual inspection, the support bars 14 of the support unit 18should be moved to be corresponded to the dummy region DR of the displaysubstrate 20.

Accuracy of the visual inspection is degraded by any shielding orblocking of inspection light by the support bars 14 or the supportingmeans 16. This generally occurs if the support bars 14 and thesupporting means 16 overlap with the active areas AA1 and AA2 of thefirst or second cells 22 and 24 as shown in region OP of FIG. 2.However, because the support bars 14 of the support unit 18 according tothe related art move by a simple rectilinear movement, small size activeareas such as the second active areas AA2 of the display substrateinevitably overlap with a portion of the support bars 14.

Therefore, there is a problem in that the visual inspection cannot beaccurate because the inspection light is shielded where the support bars14 and the supporting means 16 overlap the active areas.

SUMMARY OF THE INVENTION

Accordingly, the present invention is directed to a support unit that isutilized in a visual inspection of a display substrate thatsubstantially obviates one or more of the problems due to limitationsand disadvantages of the related art.

An advantage of the present invention is to provide a display devicethat has improved quality because of a more accurate inspection due tomitigation of light shielding during inspection.

Another advantage of the present invention is to provide a support unitfor inspection of a display device that enables more accurate inspectionof the display's active area.

Additional features and advantages of the invention will be set forth inthe description which follows, and in part will be apparent from thedescription, or may be learned by practice of the invention. Theobjectives and other advantages of the invention will be realized andattained by the structure particularly pointed out in the writtendescription and claims hereof as well as the appended drawings.

To achieve these and other advantages and in accordance with the purposeof the present invention, as embodied and broadly described, a supportunit for a display substrate, comprises first and second fixed barsdisposed apart from each other and oriented along a first direction; aplurality of support bars connected to both of the first and secondfixed bars, the plurality of support bars oriented along a seconddirection crossing the first direction and movable along the firstdirection; a guide bar disposed on at least one of the plurality of thesupport bars, the guide bar oriented along the first direction andmovable along the second direction; first and second auxiliary supportbars connected to the guide bar, the first and second auxiliary supportbars oriented along the second direction and movable along the firstdirection; and a plurality of supporting means disposed on the pluralityof the support bars and the first and second auxiliary support bars.

In another aspect of the present invention, a method of inspecting adisplay substrate using a support unit, the display substrate having aplurality of first cells having a first active area, at least one firstdummy region between the first cells, a plurality of second cells havinga second active area smaller than the first active area, a second dummyregion between the first and second cells, and a plurality of thirddummy regions between the second cells; the support unit having asupport bar, a guide bar disposed on the support bar, a first and secondauxiliary support bar connected to the guide bar, and supporting meansdisposed on the support bar and the first and second auxiliary supportbar, the method comprises disposing the display substrate on a pluralityof supporting means; aligning the support bar with one of the at leastone first dummy region; aligning the guide bar with the second dummyregion; and aligning the first and second auxiliary support bar with twoof the plurality of third dummy regions.

In another aspect of the present invention, a method of preparing adisplay substrate for visual inspection on a support unit, the displaysubstrate having a plurality of first cells having a first active area,at least one first dummy region between the first cells, a plurality ofsecond cells having a second active area smaller than the first activearea, a second dummy region between the first and second cells, and aplurality of third dummy regions between the second cells; the supportunit having a support bar, a guide bar disposed on the support bar, afirst and second auxiliary support bar connected to the guide bar, andsupporting means disposed on the support bar and the first and secondauxiliary support bar, the method comprises disposing the displaysubstrate on a plurality of supporting means; aligning the support barwith one of the at least one first dummy region; aligning the guide barwith the second dummy region; and aligning the first and secondauxiliary support bar with two of the plurality of third dummy regions.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and explanatory and areintended to provide further explanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this specification, illustrate embodiments of the invention andtogether with the description serve to explain the principles of theinvention.

FIG. 1 is a schematic perspective view of a support unit utilized in avisual inspection of a display substrate according to the related art.

FIG. 2 is a schematic plan view showing a support unit according to therelated art supporting a multi-model type display substrate.

FIG. 3 is a perspective view of a support unit utilized in a visualinspection of a multi-model type display substrate according to thepresent invention.

FIG. 4 is a plan view illustrating a support unit according to thepresent invention supporting a multi-model type display substrate.

FIG. 5 is a cross sectional view illustrating a support unit accordingto the present invention supporting a multi-model type displaysubstrate.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

Reference will now be made in detail to an embodiment of the presentinvention, example of which is illustrated in the accompanying drawings.

FIGS. 3, 4, and 5 illustrate a support unit 128 utilized in a visualinspection of a multi-model type display substrate 200 according to thepresent invention. FIG. 3 is a perspective view for the support unit128, FIG. 4 is a plan view illustrating a support unit 128 supporting amulti-model type display substrate 200 by the support unit, and FIG. 5is a cross sectional view showing a support unit 128 supporting amulti-model type display substrate 200.

As illustrated in FIG. 3, first and second fixed bars 110 and 112 aredisposed apart from each other and are oriented along a first direction.A plurality of support bars 114 are connected to both of the first andsecond fixed bars 110 and 112, and they are oriented along a seconddirection crossing the first direction. Each of the plurality of supportbars 114 are independently movable along the first direction. Inaddition, a guide bar 116 is mounted on at least one of the plurality ofthe support bars 114 and is oriented substantially along the firstdirection. The guide bar 116 is movable along the second direction.

First and second auxiliary support bars 118 and 120 are connected to theguide bar 116 and are oriented along the second direction. The first andsecond auxiliary support bars 118 and 120 are independently movablealong the first direction by a distance whose limit is in part due tothe length of the guide bar 116. Moreover, a plurality of supportingmeans 122 is mounted on the plurality of the support bars 114 and thefirst and second auxiliary support bars 120. The plurality of supportingmeans 122 may directly support a display substrate (not shown).

As illustrated in region EV, the support bars 114 having the guide bar116 thereon has a slot 124, or sliding hole, which functions as a movingchannel for the guide bar 116 that engages the slot 124. That is, theslot 124 is oriented along the second direction and the guide bar 116can move along that direction by passing through the slot 124. Inaddition, each of the first and second auxiliary support bars 118 and120 may have a variable length corresponding to the position of theguide bar 116 along the second direction. The first and second auxiliarysupport bars 118 and 120 have first and second end portions,respectively. The first end portions of the first and second auxiliarysupport bars 118 and 120 are respectively connected to the guide bar116, and the second end portions of the first and second auxiliarysupport bars 118 and 120 are respectively connected to the second fixedbar 112. In a particular embodiment, the first and second auxiliarysupport bars 118 and 120 have a separable structure such that thesupport bars 118 and 120 may be replaced with substantially similarsupport bars having a different length, as illustrated in FIG. 3.Alternatively, the first and second auxiliary support bars 118 and 120may be each connected at their respective second end portions by a mountthat permits the support bars 118 and 120 to translate along the seconddirection relative to the second fixed bar 112. Such a mount may enablethe first and second support bars 118 and 120 to vary in lengthaccording to the position of the guide bar 116 along the seconddirection. One skilled in the art will readily recognize that manyconfigurations and variations for such a mount are possible and withinthe scope of the invention.

Moreover, the guide bar 116 and the each of the first and secondauxiliary support bars 118 and 120 may be connected whereby the guidebar 116 has a concave feature (not shown) formed in one side, and thesupport bars 118 and 120 has a complementary convex feature (not shown)formed on the end that interfaces with the guide bar 116. The concavefeature may take the shape of a tab, and the convex feature may take theshape of a groove, wherein the tabs at the ends of each of the supportbars 118 and 120 may engage the groove in guide bar 116, as illustratedin region EV. With this arrangement, the support bars 118 and 120 mayindividually translate in the first direction relative to the guide bar116. It will be apparent to one of ordinary skill that many variationsto this feature are possible and within the scope of the invention.

In a particular embodiment, each supporting means 122 within theplurality has a separable structure. Each of the support bars 114 andeach of the first and second auxiliary support bars 118 and 120 have aninserting hole (not shown) where the supporting means 122 connects toeach of the support bars 114 and each of the first and second auxiliarysupport bars 118 and 120. Moreover, a connection means 126 is locatedbetween each of the supporting means 122 and the inserting hole, and canbe separated from the inserting hole. The first and second fixed bars110 and 112, the support bars 114, the guide bar 116, the first andsecond auxiliary support bars 118 and 120, and the supporting means 122combine to form the support unit 128.

An exemplary setting process of the support unit 128 for the multi-modeltype display substrate such as an LCD panel in an LCD cell processaccording to the present invention will be explained referring to FIGS.4 and 5.

In FIGS. 4 and 5, a display substrate 200 includes a plurality of firstcells 202 having a first active area AA1 in first and second rows, aplurality of second cells 204 having a second active area AA2 smallerthan the first active area AA1 and located in a third area, and a dummyregion DR defined between the first and second cells 202 and 204.

To support the display substrate 200, a support unit 128 is prepared.Next, the display substrate 200 is disposed on the support unit 128. Theplurality of support bars 114 and the guide bar 116 are moved to alignto a portion of the dummy region DR between the plurality of the firstcells 202. Then, the first and second auxiliary support bars 118 and 120are moved to align with a portion of the dummy region DR between theplurality of the second cells 204. At this point, if the distancebetween the guide bar 116 and the first fixed bar 110 is changed due toa required shifting of the guide bar 116 in order to align with thedummy region, the first and second auxiliary support bars 118 and 120may be exchanged with other auxiliary support bars having a lengthcorresponding to the required distance.

The supporting means 122 overlapped with the active areas AA1 and AA2may be separated from the support unit 128 before the step of inspectingthe display substrate 200. After doing so, the remaining supportingmeans 122 are located in positions corresponding to the dummy region DR.Accordingly, the supporting means 122 can be located such that they mayexclusively contact the dummy region DR. Therefore, shielding ofinspection light due to the support bars 114 can be reduced.

If any of the support bars 114 and/or any of the first and secondauxiliary support bars 118 and 120 overlap a portion of the small activearea due to the alignment structure of the active areas AA1 and AA2, thesupporting means 122 that overlap the active areas AA1 and AA2 can beremoved from the respective support bar.

With this done, an interval portion IP is defined between the displaysubstrate 200 and the auxiliary support bar 118 (or 120) or between thedisplay substrate 200 and the support bar 114. Inspection light can bepartially radiated onto the display substrate 200 due to the intervalportion IP. As a result, accuracy of the visual inspection can beenhanced.

Although not shown, the visual inspecting process may include radiatinginspection light onto the back of the display substrate and visuallyinspecting the display substrate, although other inspection methods,optical or otherwise, may be used with the support unit 128 inaccordance with the present invention.

As explained above, when the support unit 128 according to the presentinvention is utilized for a display substrate having various size cells,it can support the display substrate in the dummy region DR through itsthe support bars. Therefore, production quality can be increased byminimizing shielding of the inspection light.

It will be apparent to those skilled in the art that variousmodifications and variation can be made in the present invention withoutdeparting from the spirit or scope of the invention. Thus, it isintended that the present invention cover the modifications andvariations of this invention provided they come within the scope of theappended claims and their equivalents.

1. A support unit for a display substrate, comprising: first and secondfixed bars disposed apart from each other and oriented along a firstdirection; a plurality of support bars connected to both of the firstand second fixed bars, the plurality of support bars oriented along asecond direction crossing the first direction and movable along thefirst direction; a guide bar disposed on at least one of the pluralityof the support bars, the guide bar oriented along the first directionand movable along the second direction; first and second auxiliarysupport bars connected to the guide bar, the first and second auxiliarysupport bars oriented along the second direction and movable along thefirst direction; and a plurality of supporting means disposed on theplurality of the support bars and the first and second auxiliary supportbars, wherein the display substrate includes a plurality of first cells,a plurality of second cells, a dummy region between the first and secondcells, and wherein the plurality of supporting means are located toexclusively contact the dummy region.
 2. The unit of claim 1, whereinthe first and second auxiliary support bars have first and second endportions, respectively, the first end portions of the first and secondauxiliary support bars connected to the guide bar, and the second endportions of the first and second auxiliary support bars connected to oneof the first and second fixed bars.
 3. The unit of claim 2, wherein theguide bar includes a slot.
 4. The unit of claim 3, wherein the first endportions include a tab engagable with the slot.
 5. The unit of claim 1,wherein the first and second auxiliary support bars have a lengthcorresponding to a distance from the guide bar to one of the first andsecond fixed bars.
 6. The unit of claim 1, wherein the plurality ofsupporting means include a separable structure.
 7. The unit of claim 6,wherein the support bars and the first and second auxiliary support barsinclude an inserting hole to which the supporting means is connected. 8.The unit of claim 7, further comprising a connection means between eachof the supporting means and the inserting hole, the connection meansbeing separable from the inserting hole.
 9. The unit of claim 1, whereinat least one of the support bars having the guide bar thereon includes aslot.
 10. The unit of claim 9, wherein the guide bar engages the slot inthe support bar.
 11. The unit of claim 1, wherein the plurality of firstcells have a first active area, and the plurality of second cells have asecond active area smaller than the first active area.